kernel opition 'options PAE'. This will only work with device drivers which
either use busdma, or are able to handle 64 bit physical addresses.
Thanks to Lanny Baron from FreeBSD Systems for the loan of a test machine
with 6 gigs of ram.
Sponsored by: DARPA, Network Associates Laboratories, FreeBSD Systems
accessing an alternate address space this causes 1 page table page at
a time to be mapped in, rather than using the recursive mapping technique
to map in an entire alternate address space. The recursive mapping
technique changes large portions of the address space and requires global
tlb flushes, which seem to cause problems when PAE is enabled. This will
also allow IPIs to be avoided when mapping in new page table pages using
the same technique as is used for pmap_copy_page and pmap_zero_page.
Sponsored by: DARPA, Network Associates Laboratories
function.
Also, use m_defrag where appropriate to defrag long mbuf chains
in the same fashion as was done in if_sis.c. Before this change,
if_dc would blow up and take down the interface if fed a really long
mbuf chain.
MFC after: 2 weeks
a struct pmap be the same on both SMP and UP kernels.
It turns out that the size of a struct pmap is much larger on alpha
SMP systems due to the number of pm_asn's being dependant on MAX_CPU.
Since modules are supposed to be SMP agnostic, this has the affect of
moving around the "interesting bits" of the vmspace (daddr, dsize)
that the osf1 module wants to frob. So the module ends up scribbling in a
pmap struct, and the user either sees a panic, or an application failure.
While here, I've also shrunk MAXCPU to 8 now that it affects the size
of pmap structs on UP systesm. This should be plenty, as I'm
unware of any hardware we currently run in which supports more than 8
CPUs.
1. The chain passed in is > 31 fragments long
or
2. The chain will not fit in the remaining descriptors without
defragmentation.
This is slightly less clear than other network drivers because the sis
chips share one descriptor list for all packets, it seems.
Before this change, a > 127 fragment chain would get stuck in the IFQUEUE
permanently, bringing all network traffic to a halt.
MFC after: 2 weeks
Clean up the DMA interface too much unneeded stuff crept in with
the busdma code back when.
Modify the ATA_IN* / ATA_OUT* macros so that resource and offset
are gotten from a table. That allows for new chipsets that doesn't
nessesarily have things ordered the good old way. This also removes
the need for the wierd PC98 resource functions.
Tested on: i386, PC98, Alpha, Sparc64
